Many types of vehicles, and particularly utility vehicles such as lawn mowers, tractors and the like, are steered to the left and right through the operation of independently controlled drive wheels. For instance, to turn such a vehicle to the left, the left drive wheel can be slowed relative to the right drive wheel such that the greater percentage of torque produced by the vehicle's motor is transmitted to the right drive wheel. Such vehicles can be controlled through left and right control levers. Further, many of these types of vehicles are steered by a steering handle such as a steering wheel which operates a front set of wheels through a steering column.
These different types of steering provide different benefits. For example, steering through an independent drive of rear wheels using control levers allows ZTR capabilities to make the vehicle more agile and responsive. On the other hand, using a steering handle is more comfortable for the driver of the vehicle due to its familiarity.
Vehicles have been designed in the past that provide both types of steering. However, the steering handle often stays engaged creating a safety hazard for the driver of the vehicle. Others have been designed to disengage the steering column of the vehicle when the control levers are used to steer the vehicle. However, the design of such a vehicle is complicated and the steering column can be hard to work on. Failure of the disengaging mechanism can require significant disassembly of the vehicle.
It would therefore be advantageous to provide apparatuses and methods for steering a vehicle using a steering wheel controlled transmission system, and also to provide an ability to steer a vehicle at a zero turn radius that is easy to operate and maintain.